When surgery is indicated to remove a lesion in tissue or a biopsy sample is to be obtained, the location of the lesion must first be determined in some manner. With lesions that can be palpated intraoperatively or can be directly visualized, video assisted thoracic surgery is a minimally invasive endoscopic procedure that is preferred over open thoracotomy. With respect to small lesions in certain tissue such as lung tissue, however, it is sometimes difficult for the surgeon to directly localize the lesion to be excised, such as where the lesion is located deep in the pleura or in the posteriomedial aspect of the lung. Further complicating the procedure may be coexisting lung diseases such as pulmonary fibrosis, and the change in geometric relationships caused by the intentional collapse of the lung during the procedure. In these cases, it is usually desirable to mark the lesion with a localizing device of some type.
By one approach for marking lesions in the breast and in the lungs, a wire probe is introduced at the site of the lesion through an introducer needle after the lesion has been located radiographically. The distal end of the probe is typically placed through the lesion, allowing the wire to be braced against the lesion. With conventional localizing wires, however, the wire has a tendency to pull away from the lesion, particularly when the lesion is small or is located in lung tissue which is significantly less dense than breast tissue. Dislodgement of the wire can occur in several ways. For instance, when the patient is transported to surgery the wire may accidentally be pulled out of position as the chest wall and shoulder girdle are moved. The wire may also become dislodged when the lung is deflated prior to removal of the lesion, or when retraction is applied on the wire to tent the lung to allow easier access to the resection site. Some localization wires in the prior art have the further limitation in that they are not repositionable after they have been deployed.
There is a need for a lung lesion localization device that will not dislodge from tissue after deployment, which provides sufficient holding power so that retraction may be applied, and which further allows for repositioning when desired. The present invention addresses this need.